Did you use compress back up? If that is the case, it is expected to fail as the data size may be more than 145GB that is available. Also like Rick said, please check the data and log size of the database.

There is no rule defined for how much size is needed to restore. Like I said in the above post, please check for data and log files or in other words check the size of DB before backing up and ensure you have the same size available while restoring it.

In your object browser right mouse click on the database you just backed up, select properties, select General, look at the Size of the database; That is how much space you need on your target machine if you need to restore that database.